1. Field of the Invention
The present invention relates to a processing method for a package substrate having a plurality of semiconductor chips molded with resin.
2. Description of the Related Art
In a semiconductor device fabrication process, a plurality of semiconductor chips each having a circuit such as an LSI are mounted on a leadframe or a printed board, and each electrode is connected by bonding. Thereafter, these semiconductor chips are molded with resin to thereby form a package substrate such as a CSP (Chip Size Package) substrate and a BGA (Ball Grid Array) substrate. Thereafter, the package substrate is diced-cut by using a cutting blade or the like to manufacture a plurality of individual semiconductor devices molded with resin. Such semiconductor devices are widely used for electronic equipment such as a mobile phone and a personal computer.
With a recent reduction in size and thickness of electronic equipment, a reduction in size and thickness of each semiconductor device is also earnestly desired. Therefore, in a semiconductor device fabrication process, there is a desire such that a resin molded surface of the package substrate having the semiconductor chips molded with resin is ground to reduce the thickness of the package substrate. In grinding the package substrate, a grinding apparatus called a grinder as disclosed in Japanese Patent Laid-open No. 2008-272866, for example, is widely used. Such a grinding apparatus includes a holding table for holding a workpiece such as a package substrate under suction and a grinding wheel opposed to the workpiece held on the holding table, wherein the grinding wheel is brought into sliding contact with the workpiece to thereby grind the workpiece.